Multi-stage projectile



Feb. 2, 1960 R. J. FISSEL MULTI-STAGE PROJECTILE Filed May 12. 1958 INVENTOR.

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un". 2 la' RUSSELL J FISSEL AGENT United States Patent O MULTI-STAGE PROJECTILE Russell I. Fissel, Southamptomla.

Application May 12, 1958, Serial No. 734,767

5 Claims. (Cl. 46-74) This invention relates to a multiple unit projectile and more particularly, although not necessarily exclusively to a multi-stage spring actuated rocket assembly.

Known prior art devices of the aforedescribed category have for the most part been single stage units in which the energy required for launching or catapulting has been variously derived from explosive charges, compressed air or a spring. In each instance, however, with the possible exception of weapons of war, the apparatus has generally taken the form of a single unitary assembly utilizing either a base structure for housing the launching mechanisms or consists of a device wherein the propulsion apparatus is housed within the rocket assembly itself.

In order to produce sufcient force or power to launch a device of the foregoing self-propelled type into the air,

a relatively large diameter stiff spring is used or where overall body length is of slight consideration a long narrow relatively flexible coiled spring is employed. Those rocket assemblies wherein the air borne unit is separable from the propulsion unit, generally utilize a platform structure which also acts as a housing for the required power plant. Such latter propulsion means may consist of a compressed air pump, reservoir and trigger mechanism, or, a relatively large coiled spring and a release mechanism, o-r in some instances the combination of a spring and air actuated device. Some known rocket projectiles combine a coiled spring housed within the rocket assembly with a coiled spring contained within a base supporting structure on or into which the assembled rocket is initially loaded.

In any case, the motive force whether spring, explosive charge or compressed fluid, i.e., air or gas, is limited by the initial size of either or both the rocket device and the launching mechanism. This latter power limitation can be circumvented somewhat by increasing the number of spring coils, lengthening and/ or stiifening the springs, increasing air pressure etc. Such methods however, are relatively unsatisfactory and have resulted generally in apparatus which'is bulky, cumbersome and unwieldly to handle.

It is an important object therefore of the present invention to provide a multi-stage rocket assembly which overcomes the foregoing difficulties in a new and unusual manner.

Still another object of the present invention is to provide an improved multi-stage rocket assembly having relatively few parts which is simple and economical to fabricate and assemble. Y

A still further object of this invention is to provide a multi-stage rocket assembly capable of automatically launching one or more stages, as desired.

An additional object of the invention is to provide a multi-unit projectile having a plurality of separable, interconnected portions, eachl portion being separated from the next adjacent portion under the combined acceleration provided from a self contained power unit and the forward thrust of the previous stage or unit.

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Another object of this invention is to provide a multiple unit projectile whose component units automatically separate in ight, release of each unit being triggered by means of an individual latch which is carried in each of the units making up the rocket assembly.

A preferred embodiment of the multi-stage projectile constructed in accordance `with the teaching of the present invention comprises a plurality of sub assemblies or stages which are telescopically slidably assembled together and disposed upon a projectile supporting-launching structure or base. Each stage is self propelled by means of a coiled spring which is or may be housed externally or internally of the stages, or both, if desired. Each stage is provided with a latch-release mechanism adapted to engage the next preceding unit or stage. The base or launching pad is provided, in addition to its own latchreelase mechanism, with a trigger device adapted to release all of the stages substantially simultaneously, at will. Launching of the releasably connected stages from the base actuates each latch-release mechanism whereupon the final free flight stage becomes airborne.

Other objects and advantages of the present invention will be apparent from the following detailed description taken in conjunction with the accompanying drawings in which:

Fig. 1 is a sectional view inside elevation of the assembled multi-stage projectile of the present invention;

Fig. 2 is a view similar to Fig. l but showing the stages slightly separated as they would appear immediately after launching;

Fig. 3 is a detail View taken along line 3--3 of Fig. l;

Fig. 4 is a partial section detail within the dotted outline 4 of Fig. 1 showing the latch-release mechanism of the present invention;

Fig. 5 is a detail sectional view of the latching mechanism of the invention, the View being taken along the line 5-5 of Fig. 1; and

Fig. 6 is a sectional View taken along the line 6--6 of Fig. 1 illustrating the trigger launching mechanism of the invention.

Construction Referring trst to Fig. l, a preferred embodiment of an assembled multi-stage projectile constructed according to the present invention is seen to comprise four main parts, units or stages as follows: launching base 10, a rst movable stage 12, a second movable stage 14 and a third or final free Hight stage 16. Only three movable stages are shown in the present embodiment, however, it is to be understood that any number of stages may be used with this invention, the number of stages being limited by the desired size and handling ease of the nal assembly. v

The launching pad, hereinafter referred to as the base 10, is or may be fabricated from any suitable material having suiicient rigidity to withstand the initial surge of pressure developed at the instant of release of the three movable stages.

With the exception of the base lil, the three stages 12, 14 and 16 are substantially similar in construction, certain exceptions being noted hereinafter. Each stage is fabricated from suitable light weight material having sucient rigidity to be formed or shaped into a hollow cylinder or tube, for example, as shown. The shape is a matter of choice.

In Fig. 1 it can be seen that the three stages which are to be launched from the base 10 are each constructed so. as to provide a portion which is capable of being telescopically interfitted with the next adjacent stage including the base upon which the assembled projectile is initially loaded. Each stage beginning with the free ight stage 16 to and includingk the stage 12, consists ofja hollow tubular member of graduated and decreased diameter, as shown. The open end portion 18, of member 16 is telescopically slidably received over the upper narrow reduced portion of member Likewise,V the open end 20 of member 14 is slidably received over member 12. Member 12 in vturn has its open end 22 slidably received over the lowermost upst'anding hollow cylindrical launching guide tube member 24 which is secured tothe launching base 10.

Launching base As can be seen from Figs. 1 and 2, the launching base 10 comprises a supporting member such as a plate of any suitable rigid material e.g., wood, metal, plastic etc., to which is secured the aforementioned launching guide tube 24. The specific choice of the various projectile parts is or may be determined on the basis of cost, weight, ease of handling and fabrication. A trigger shaft 26 is axially rotatable within the guide tube 24 and is controlled by means of a trigger handle 28 threadedly or otherwise secured thereto through the arcuately elongated slot 30 in the tube 24. A coiled trigger return spring 32 biases the trigger handle 28 into an inoperative position, as will hereinafter be described. A trigger spring 34 of suitable resilient materialv is secured to the baseplate 10 as by a screw 36. The upstanding portion of the unsecured end.

of the trigger spring is inwardly bowed or bent as indicated by reference character 38 and is initially biased so as to project inwardly of the assembly through a slot 40, Fig. 5, in the guide tube 24 so as to rest in its untensioned or relaxed condition against slanting cam surface 42 of Fig. 2 ofthe trigger shaft 26. The terminal end of the trigger spring 34 is hook shaped as shown by reference character 44 for latching engagement with guide pin and trigger catch 44 disposed in stage one for a purpose to be described later on. Rotation of the trigger handle will cause the slanted cam surface 42 to move or ,cam the hook shaped spring end 44 outwardly through the slot 40, Fig. 5, away from the guide tube to snap over the aforementioned pin 4S. A notch or recess in the upper end of the trigger shaft 26 permits the shaft 26 to be locked in place after rotation from the position of Fig. 1 to that of Fig. 2 cocking the mechanism as hereinafter described. The upper end of the trigger shaft 26 is also provided with an eyelet 48 or other similar means for attachment thereto of a cable 50 the purpose of which will appear more clearly hereinafter.

First stage The first stage 12 comprises a hollow cylindrical projectile shell having an elongated portion 52 slidably receivable over the guide tube 24 of the launching base 10. A cylindrical trigger or piston rod 54 slidable within the reduced upper portion compressing the first stage guide tube 56 is provided with a piston 58 of suitable material, such as Bakelite, at one end thereof. A piston return spring 60 provided with a prescribed slight initial compression s'urrounds the piston rod and is seated against and retained by the piston S at one end and the shoulder 62 of the opposite end of the rst stage shell.V A guide pin and trigger catch 64, Fig. 4, projects through the guide tube 56 for a purpose to be described presently. The bottom surface of the piston 58 rests against guide pin 45 when the spring 60 is in its initially compressed or uncocked condition. The hook shaped end of trigger spring 34 in the base 10 engages pin 45 when the assembly is cocked as shown in Fig. l and as will become more apparent as the description proceeds. Secured to the shell, as shown at 68, is a trigger spring 66 substantially identical to spring 34 in the launching base 10. The free end of spring 66 including its inwardly bent or bowed portion 70 and the hooked end 72 projects inwardly of this shell through a slot 74, Fig. 4, in the lower end of the .guide tube 56 so as to rest when in its relaxed condition as shown in the dotted outline of Fig. 4. An eyelet 78 similar to eyelet 48 is secured to the frusto conical end 76 of the piston rod for the securement thereto of a cable 80 similar to cable 50. Eyelet 75 on the piston 58 permits the cable 50 to join the launching guide tube 26 to the first stage for purposes to be explained later on.

It is apparent from the foregoing that telescopic compressive movement of the piston and piston rod, i.e., compressing spring 60, as in cocking the assembly, will cause the frusto conical portion 76 to force the trigger spring 66 outwardly through the slot 74 causing the hook shaped end 72 to snap over the guide pin 64 locking the first stage to the launching base 10.

Second stage Still referring to Figs. l and 2, the second stage 14 is seen to comprise a hollow cylindrical shell 82 having a reduced upper end portion forming a second stage guide tube 84. A trigger or piston rod 86 carrying a piston 88 at one end thereof, is provided with a piston return spring 90 one end 92 of which abuts the inner surface of the piston while the opposite end of this spring abuts the shoulder 94 at the base of the guide tube 84. A trigger spring 96 substantially identical to the springs 34 and 66 is secured to the shell 82 as at 98 while the upwardly extending inwardly bent portion 100 and the hook shaped end 101 thereof, projects through a slot 102 in the guide tube 84. A guide pin and trigger catch 103 is disposed in the lower portion of stage three. The piston 88 rests against pin 64 when spring 90 is uncocked. As with the preceding stage compressive movement of the piston 88 and piston rod 86 as by mounting on this stage as on the preceeding stage will force the frusto conically shaped end of the piston rod against the trigger spring 96 moving the hook shaped end 101 outwardly through a slot 102 within which it is disposed, to engage the pin 103 and latch this stage to the preceding lower stage. An eyelet 106 is or may be used for the attachment thereto of the cable 80 for a purpose presently to be explained.

Third, free flight stage The third or final free flight stage 16 comprises a hollow cylindrical shell 112 carrying a launching spring 114 retained therein by means of the guide pin and trigger catch 103, Fig. 2, at one end thereof and the end wall 118 of the shell at the opposite end. Y y

Stage 116 is designed for free air ight and to this end it is provided with an aerodynamically shaped nose cone 120 which is or may be provided with a hollow chamber 122 for carrying a lowering parachute permitting the recovery of the stage without undue damage due to the shocks incurred during rapid descent or on contact with the earths surface. Additionally, the third stage is or may be provided with a plurality of laterally projecting guidance surface members 124 forming air foils for greater sustained free flight and to prevent or reduce rotative or twisting motion after launching. Such guidance members can be fabricated integrally with the shell 112 or they may be secured thereto in any suitable and well known manner.

y It may be desirable in some instances to load the nose cone chambers with a low velocity explosive charge in which case it is necessary to make provision forpreventing any blow back from deleteriously effecting Vthe mechanism within the central body portion of this stage as by fabricating the nose cone itself from light weight metal or similar material. p

In order to provide for proper and accurate orientation of the various stages one with another, and with the launching base 10, launching guide tube 24 and first and second stage guide tubes 56 and 84 are each provided with an elongated flat surface portion 126 and 128 respectively, extending the length of each guide tube. Only the flat surfaces of guide tubes 24 and 56 being shown in the drawing. Since each shell will matingly t or be received over only one guide tube, the flat surfaces prevent any accidental misalignment of stages. In addition' since the flat surfaces are formed on the same sides of the guide tubes as that on which the trigger springs are each located, the possibility of failure of the trigger spring to latch withits mating guide pin is thus avoided.

Time delay is designed and built into the present invention and is or may be varied by means of the piston rods whose length may be altered or changed to suit the specific conditions desired. Delay may also be provided through the medium of individual orifices not shown, in the pistons 58, 88 respectively. Each orifice is or may be provided with an adjustable air bleed screw, also not shown, so that a desired exact and measured amount of air can escape from the shells 12 and 14 during the expansive release of the springs 60 and 90, respectively during launching.

In order to assure that the three stages when loaded and cocked onto the base will not be accidentally'dislodged or slip into a release or launching condition, the upper surface portion of the base trigger shaft 26 is provided as before noted, with the notch or nick 46 into which the spring 34 will positively seat or engage.

Loading operation With the base guide tube 24 disposed in a vertical position, e.g., as shown in Fig. 2, the first stage 12 is placed on guide tube 2450 that the guide pin and trigger catch 45 is in substantial alignment with the fiat side 126 of the base guide tube 24 and the piston 58 in position to seat upon the upper end of the tube 24. The second stage 14 is then telescopically slidably received on the guide tube 56 of the first stage 12 so that guide pin and trigger catch 64 are in alignment with the flat side 12S of the first stage guide tube 56. The third or final stage 16 is placed on the guide tube 84 of the second stage so that guide pin and trigger catch 103 is in alignment with the flat side (not shown) of the second stage guide tube 84. The three stages are now ready to be cocked. The third stage 16 is pressed downwardly until it bottoms on or abuts the next lower stage which causes the spring 114 to be compressed. As the third stage continues its downward movement the trigger catch pin 101 passes the plunger end 110 just prior to the trigger spring 96 which then rides along the conical part of the plunger to be pressed outwardly to latch over the pin 101. With these two stages held together the third and second stages are pressed downwardly onto the first stage compressing each of the second and first stage springs 90 and 60 to thereby latch the stages together in the manner described for the latching of the third stage to the second stage.

The downward travel of stages 12, 14 and 16 relative to the pistons 58 and 88 forces each of the irusto conical end portions 76 and 110 to engage and press outwardly the respective springs 66 and 96 with its respective hook shaped end portion 72 and 101. Each portion 72 and 101 of each spring is thus permitted to snap over its associated guide pin 64 and 103. Arcuate rotation of the trigger handle 28 through cam 42 presses the lower trigger spring 34 outwardly causing its hook shaped end 44 to snap over the guide pin 45 thus latching i.e., cocking the three stages together as a unitary but automatically separable assembly.

Firing The trigger handle 28 which may be moved remotely or by hand as desired, is turned to its uncooked position, Fig. 2. As the handle turns, the trigger spring 34 spring,s back into the slot 40 in the side wall of the tube 24. This action releases the hook shaped spring end 44 from the guide pin 4S causing the first stage 12 to be ejected under expansion of the stored energy of the piston return spring 60 which compressive force has now been released. This force launches the three stages 12, 14 and 16 in the direction of the arrow 132, substantially together. When the stage 12 has moved approximately 95 of its travel,

it releases the trigger spring 66 and the second and third stages are launched together, arrow 134.

When stage 14 has travelled for approximately 95 of its travel the trigger spring 96 is released from its guide pin 103 and the third stage is launched into free ight, arrow 136. The third stage is aided in its upward movement by the additive force of its own launching spring 114 which was also under compression as earlier described but now released to propel the projectile outwardly away from the other stages.

The first and second stages are easily recoverable by means of the cables which may be used therewith. Suitable bright colors can be used to mark or identify the third stage to prevent its accidental loss after launching.

What is claimed is:

1. A multiple stage projectile of the character described comprising, a fixed base, a guide member upstanding from said base a first stage telescopically slidably mounted on said guide member, a second stage telescopically slidably mounted on said first stage, a third free flight stage telescopically slidably mounted on said second stage, means releasably securing together said second and third stages, means releasably securing said second stage to said first stage, means releasably securing said first stage to said base, self-propelling means in each stage, a trigger in said base operable to release said securing means to eject said first stage from said base by said propelling means, means disconnectibly releasing said second and third stages While in flight by the self propelling means within said stages acting upon said means securing said stages together.

2. A multiple stage projectile comprising, a fixed launching base, an upstanding guide member rising from said base, a first stage tube slidable on said member, a releasable latch connecting said tube to said base, means including a compression spring to eject said tube when said latch is released, means operable at will for releasing said latch to eject said tube by said spring, a second stage tube slidable on said rst stage tube, a releasable latch connecting said tubes together, means actuated by the ejecting movement of said first stage to release said second stage latch, and means including a compression spring for ejecting the unlatched second stage from the rst stage, whereby the two stages are successively ejected for free flight.

3. A multiple stage projectile according to claim 2, wherein third stage member is slidable on said second stage tube, a releasable latch connecting said third stage member to said second stage tube, means actuated by the ejecting movement of said second stage for releasing the latch of said third member, and means to propel the released third stage member.

4. A multiple stage projectile comprising a fixed base, a guide member rising from said base, a closed end first stage tube telescopically slidable on said member, a latch connecting said tube and said member in telescoped condition, a piston in said tube, a piston rod projecting through said closed end, a spring compressed between said piston and said end to eject said tube when said latch is released, trigger means in said base to release said latch, a second stage tube telescopically slidable on said first tube, a latch connecting said tubes in telescoped condition, and means controlled by said piston rod for releasing said second tube latch in response to the ejecting movement of said first stage tube.

5. A multiple stage projectile comprising a fixed launching base, an upstanding guide member rising from said base, a first stage tube telescopically slidable on said guide member, a second stage tube telescopically slidable on said first tube, a third stage tube telescopically slidable on said second tube, a releasable latch connecting said second tube with said first tube in telescoped condition, a releasable latch connecting said third tube with said second tube in telescoped condition, propelling means in each stage tube, means including rod carried pistons respectively in said tubes for setting said prpellng means, means carried by said pistons for successively releasing said latches by the propelled movement of said tubes, a latch connecting said rst stage tube to said guide tube member, and trigger means to release' said rst stage latch to respond to the propelling means whereby the successive ejection of the second and third tubes releases the respective latches.

References Cited in the tile of this patent UNITED STATES PATENTS Fields Feb. 21, 1956 Greenwood June 26, 1956 Jablansky Sept. 3, 1957 Teague Apr. 8, 1958 

